Interior Secretary Mar Roxas on Sunday ordered the police and the military on heightened alert after an explosion at a restaurant in Cagayan de Oro City killed six people and injured 48 others on Friday night.

The death toll from the explosion is expected to rise, with one of the injured, Reynaldo Dalupan, a resident of Metro Manila, already “brain dead” in the hospital, the Inquirer learned on Sunday.

Most of the victims are doctors and pharmaceutical representatives who were celebrating at the restaurant in a popular city arcade after a national medical convention.

President Aquino condemned the attack and ordered a “clean investigation,” according to his deputy spokesperson Abigail Valte.

Clean investigation means in accordance with due process, Valte explained.

The President ordered the police to determine the motive and identify the mastermind behind the attack, she said.

“We are doing everything (to determine the suspects),” Roxas said on dzBB radio. “We have placed the police in Mindanao, the intelligence community and the Army on heightened alert to prevent a similar attack.”

Investigators have yet to determine the explosive used in the attack, which hit Kyla’s Bistro in Rosario Arcade, just outside the popular Limketkai Mall.

At least 100 doctors and pharmaceutical representatives were in the bistro celebrating after attending a national convention in a nearby hotel when the explosion occurred.

Contrary to earlier reports, Roxas said investigators had not found shrapnel or metal fragments at the blast site, which would have indicated an explosive device made from a mortar bomb.

“According to the doctors who did the autopsy report, there were no shrapnel that could be attributed to a grenade explosion,” Roxas said.

Also contrary to earlier reports, what went off was not an improvised explosive device, Roxas said.

“The (explosive) used was really different because it did not have shrapnel … or metal parts like in grenades or claymore mines,” he said.

“In other words, the bomb was not a mortar round or an artillery round, which was set off by a detonator, because no metal parts were recovered. It did not contain nails, glass shards or metal balls, which are usually placed inside a bomb to hurt people.”

Roxas said those killed died from concussions caused by the enormous “pressure wave” generated by the explosion.

Those who were injured were hit by debris from shattered furniture and other objects that the explosion sent flying all over the place.

Ordnance experts found wires and a 9-volt battery but not much else because owners of businesses in the arcade had the place cleaned up Saturday morning before police crime scene investigators could start their job.

Not Moro insurgents

Roxas’ statement suggested the attack might not have been the work of Moro insurgents who operated in other parts of Mindanao and were known to use mortar rounds as bombs by rigging these to timing devices.

When asked whether investigators were looking at any specific group behind the blast and what the motive could be, Roxas said, “If it’s business rivalry, fighting over land, or terrorism we could not say yet until we know all the facts and details.”

One of the six dead is a local politician, Misamis Oriental Board Member Roldan Lagbas.

Malacañang appealed to the public not to speculate about the motive for the attack.

The explosion has set off talk that it was aimed at derailing peace talks between the government and the Moro Islamic Liberation Front (MILF) and at embarrassing President Aquino, who was then playing host to Japanese Prime Minister Shinzo Abe.

“Some motives have surfaced, but at this point, we will defer to the investigation,” Valte said.

Roxas said he had ordered the police to reconstruct the crime scene and try to find more evidence.

He said he also ordered background checks on the dead and injured to determine if any of them was the target.

While Lagbas was a politician, Roxas said he might also not have been the target but just a victim. “Maybe the target was somebody who had moved to another place when the bomb exploded,” he said.

He said police investigators were interviewing waiters at the bistro and National Bureau of Investigation agents were talking to the injured in area hospitals.

“We are interviewing the victims and all possible witnesses. We are collating eyewitness accounts for us to reconstruct the crime scene and determine who was sitting where at the time of the explosion,” Roxas said.

He said the police would release the sketch of the man who was seen leaving a bag on a chair “in the proximate area of the blast.”

Police were reviewing video from security cameras in the place “to see the people going in and out of the area where the explosion happened,” Roxas said. The cameras are inside the bistro, but police still had to find footage that would show possible suspects.

Of the 48 injured, only two—Dalupan and Marciano Agustin—remained in intensive care in the hospital. Dalupan, who is from Manila, is an executive at the pharmaceutical company Unilab.

Agustin is a doctor who lives in Cavite province. When the Inquirer went to the hospital to ask about his condition, a source there said he was already “brain dead.”

The families of Dalupan and Agustin declined interviews.

Cagayan de Oro Mayor Oscar Moreno called on the public to refrain from speculating about the motive or perpetrator of the attack and instead wait for the result of the investigation.

In Zamboanga City, Lt. Gen. Rey Ardo, chief of the military’s Western Mindanao Command, described as “farfetched” reports linking the explosion to the Moro National Liberation Front (MNLF). “That’s too far,” he told the Inquirer by phone.

The MNLF is unhappy about the preliminary peace agreement between the government and the larger MILF and has reportedly threatened to declare “independence.”

Some 100 MNLF members gathered at the house of their leader, Nur Misuri, on Thursday, but did not make any declaration.—With reports from TJ A. Burgonio in Manila; JB Deveza, Bobby Lagsa, Julie S. Alipala and Nash B. Maulana, Inquirer Mindanao

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